#!/bin/bash


#test001
s1_generate_a_series_of_files() {  
    for i in {1..100}; do  
        echo "$i" > "/tmp/new_file$i"  
    done  
}

s2_list_4_files_in_long_format_about_account_and_group() {  
    files=("/etc/passwd" "/etc/group" "/etc/shadow" "/etc/gshadow")  
    for file in "${files[@]}"; do  
        ls -l "$file"  
    done | sort  
}


function s3_find_items_related_to_given_username() {
grep -h $1 /etc/{passwd,shadow} |sort -d
}
# s4_find_items_related_to_given_group_name  
function s4_find_items_related_to_given_group_name(){
local group_name=$1  
    local files=(/etc/group /etc/gshadow)  
    for file in "${files[@]}"; do  
        grep -h "^$group_name:" "$file"  
    done | sort
} 
  
# s5_create_groups_for_given_group_names  
s5_create_groups_for_given_group_names() {  
    local groups=("rnd" "itoperation")  
    for group in "${groups[@]}"; do  
        groupadd "$group"  
    done  
}  
s6_create_users_and_set_their_group_as_required() {  
    users=("adam" "bob" "calvin" "david" "edward")  
    primary_groups=("users" "users" "users" "users" "users")  
    supplementary_groups=("rnd" "rnd" "itoperation" "itoperation" "rnd")  
      
    for i in "${!users[@]}"; do  
        useradd -g "${primary_groups[$i]}" "${users[$i]}"  
        usermod -aG "${supplementary_groups[$i]}" "${users[$i]}"  
    done  
}

s7_change_users_shell() {  
    users=("adam" "edward")  
    for user in "${users[@]}"; do  
        usermod -s /usr/bin/sh "$user"  
    done  
}

s8_set_password_change_policy() {  
    local usernames=("adam" "bob" "calvin" "david" "edward")  
    for username in "${usernames[@]}"; do  
        chage -M 60 -m 10 -W 10 "$username"  
    done  
} 

function s9_set_password_for_five_users(){
usernames=(adam bob calvin david edward)
for i in $(seq 1 5);do echo ${!i};echo $(( $i-1 ));done
echo "${usernames[0]}:$1" | chpasswd
echo "${usernames[1]}:$2" | chpasswd
echo "${usernames[2]}:$3" | chpasswd
echo "${usernames[3]}:$4" | chpasswd
echo "${usernames[$(( $i-1 ))]}:$5" | chpasswd
}

s10_lock_bobs_password() {  
    passwd -l bob  
}

# s11_include_adam_into_wheel_group  
function s11_include_adam_into_wheel_group(){
usermod -a -G wheel adam
}
function s12_change_files_permission() {
for i in {1..33};do chmod -R 640 /tmp/new_file$[3*i];done
}
